Sodium cocoyl isethionate is a known surfactant. Its main use has been in formulating personal hygiene detergent bars. Long chain alkyl dimethylamine oxides are also known surfactants having excellent foaming properties. Their use in formulating toilet soap bars has been limited by the fact that they have only been available as aqueous solutions containing about 30 weight percent of the active alkyl dimethylamine oxide. When used to prepare toilet soap, this leads to an excessive amount of water which must be removed. Heating to evaporate this water can lead to decomposition of the amine oxide which is not thermally stable at temperatures much over 100.degree. C. At lower temperatures under vacuum, frothing presents a problem.
Recently a practical method of making long chain alkyl dimethylamine oxide dihydrates has been discovered. This process is described in U.S. patent application Ser. No. 344,275, filed Apr. 26, 1989. This discovery has made it practical to include alkyl dimethylamine oxides in toilet detergent bar formulations.
Lime soap dispersancy is the ability of a detergent to prevent deposition of insoluble lime soap when a fatty acid soap-containing composition is dissolved in water containing calcium and/or magnesium cations. Such deposits lead to the scum frequently seen in sinks and bath tubs. A need exists for a soap composition that resists such formations.